This question and its answers (copied below) provide a solution for handling the back button in Ionic, but that solution only works when other pages are pushed directly from app.component, in which case calling canGoBack and getActive() on this.nav works correctly because other pages have been pushed using this.nav.push in app.component.
However if a page is pushed from one of the pages in the tabs (lets call it page1), i.e. by calling this.navCtrl.push() in page1, then this.nav.canGoBack() in app.components still resolves to false because the push happened using the page1's this.navCtrl.push() not app.component's this.nav.push().
How can I detect inside app.components if a page was pushed from any of pages in the tabs?
platform.registerBackButtonAction(() => {
if(this.nav.canGoBack()){
this.nav.pop();
}else{
if(this.alert){
this.alert.dismiss();
this.alert =null;
}else{
this.showAlert();
}
}
});
});
}
Related
Working on a Project and stuck in an Issue:
Hardware Back Button Reloading Application (I am using Angular Router in this application).
My Code to Exit Application:
ionViewDidEnter(){
this.subscription = this.platform.backButton.subscribe(()=>{
navigator['app'].exitApp();
});
}
ionViewWillLeave(){
this.subscription.unsubscribe();
}
While same logic Working in other applications. but in this application its reloading the application not exiting it.
P.S: i have also tried it to put in platform.ready() but no luck.
With IONIC 4, there is new method subscribeWithPriority developed to handle race between soft & hard back button. Try modifying your code like below:
this.platform.backButton.subscribeWithPriority(1, () => {
navigator['app'].exitApp();
});
subscribeWithPriority() stops the propagation of the event after its execution and if we subscribe with high priority and execute our prefered navigation instead of default one then it is going to work as you want.
More reference docs for details:
https://github.com/ionic-team/ionic/commit/6a5aec8b5d76280ced5e8bb8fd9ea6fe75fe6795
https://medium.com/#aleksandarmitrev/ionic-hardware-back-button-nightmare-9f4af35cbfb0
UPDATES:
Try using this new version of exitApp cordova plugin. I haven't
tried myself but looks promising from popularity.
Also try to empty the page stack from Navcontroller or go to your home screen, seems like that's causing the reload for app with sidemenu's & tab pages... this.navCtrl.pop() / this._navCtrl.navigateBack('HomeScreen'), and then call exitApp.
NOTE: Tabs & SideMenu as those have its own routing module does create lot of complexity with app navigation.
Solved:
As Mention by #rtpHarry template of SideMenu / Tabs have History which leads application to Reload it self on root page. i was able to solve this by clearing History.
ionViewDidEnter(){
navigator['app'].clearHistory();
}
on Your Root Page just Clear your history and your Hardware Back Button will close the Application instead of Reloading it.
Do you have a sidemenu in your app? I'm just curious because this seems to be when I get this problem as well.
If you look in your inspector, you will see that window.history has a length of 1.
I don't see it in some of my apps, but the app that I have a side menu setup acts this way - on the homepage if you press back the screen goes white then it reloads the app.
Like I say, looking in the inspector shows that there is a history to step back to, which it is trying to do, and whatever that history step is, it just pushes it forward back to the homepage, which made me wonder if it was the sidemenu setting up its own control of the navigation system.
I've probably said some poorly worded terminology but as I haven't solved this myself I thought I would just let you know what I had found... hopefully it helps you move forward.
In my scenario, I wasn't even trying to do the exit on back code - I just noticed that the app would appear to "reboot" if I kept pressing back.
This explain the solution on Ionic 5 (and 4.6+ too I think).
private backButtonSub: Subscription;
ionViewDidEnter() {
this.backButtonSub = this.platform.backButton.subscribeWithPriority(
10000,
() => {
// do your stuff
}
);
}
ionViewWillLeave() {
this.backButtonSub.unsubscribe();
}
also keep
IonicModule.forRoot({
hardwareBackButton: true
}),
to true (default) in your app.module.ts
Sources:
https://www.damirscorner.com/blog/posts/20191122-CustomizingAndroidBackButtonInIonic4.html
The Doc
I've got a single html with 5 pages + navbar. To force a refresh of one page I use this:
$("#page3").on("pagecreate", function(e) {});
It works the first time, but I want it to update every time I visit the page. I know there is .trigger("create"), and "refresh", but I can't get it to work properly...
jQuery Mobile 1.4.0
You need to listen to pageContainer event in order to determine which page is active and accordingly run the functions you want.
The new events can't be attached to a specific page, unlike successor versions of jQuery Mobile. Once an event is occurred, retrieve ActivePage's ID.
$(document).on("pagecontainerbeforeshow", function (e, ui) {
var activePage = $.mobile.pageContainer.pagecontainer("getActivePage")[0].id;
if(activePage == "page3") {
doSomething();
}
});
Demo
I will try to explain this as clearly as possible. I have an android app using web view to basically load a webpage as my app. I have everything working great, however the back button seems to be an issue. I have set this page up all on one html page, it will load in a div when certain buttons are clicked to give the feel of a new page without actually having one. I basically want the back button (on the android tablet or smartphone) to load the previously loaded div, but I have no idea where to start with this. Here is what the content switching jquery looks like -
function contentSwitcher(settings){
var settings = {
contentClass : '.contentToLoad',
navigationId : '#sideMenu',
servFront : '#clickHomeHome'
};
//Hide all of the content except the first one on the nav
$(settings.contentClass).not(':first').hide();
$(settings.navigationId).find('li:first').addClass('active');
//onClick set the active state,
//hide the content panels and show the correct one
$(settings.navigationId).find('a').click(function(e){
var contentToShow = $(this).attr('href');
contentToShow = $(contentToShow);
//dissable normal link behaviour
e.preventDefault();
//set the proper active class for active state css
$(settings.navigationId).find('li').removeClass('active');
$(this).parent('li').addClass('active');
//hide the old content and show the new
$(settings.contentClass).hide();
contentToShow.show("slow");
});
}
contentSwitcher();
});
note: I've cropped out a bunch of it just to show how it works on a basic level.
Does anyone have any suggestions as to where to begin. I'd just like the back button function to be able to maybe check a started previous div name stored somewhere and load that.
thanks!
You can try using the History API. There are numerous tutorials on the web e.g. this one is quite good:
http://diveintohtml5.info/history.html
Basically this is how it works. When the user clicks the link for the div to show you push the state to the history stack.
history.pushState({<object with any information about state>}, pageTitle, newUrl);
This will push the state to the history stack meaning that when the user presses the back button on any modern browser like webkit it will take that state into consideration. When back action is taken it will then pop the state from the history stack. This action you have to listen to and handle in any way you see fit:
window.addEventListener("popstate", function(event) {
// event object contains the information from the pushed state
// do whatever needed to load the previous page here
});
The History API requires you to structure your code in a certain way for it to work well. For this I would recommend to use some existing framework that handle the back events for you e.g. Backbone.js. Hope this helps.
In my Phonegap app, created in a single html file using div as pages, I override the Back button to exit the app, only if the div that acts as the Home page is visible, otherwise to hide the others and show the home div. I use jQuery to attach the event handlers.
It works well at first app launch, but if the app is in the History list, the override is not working, the Back button exits the app without checking which div is visible. After deleting the app from the History list it works as expected again.
Tested on Nexus 4 with Android 4.2.
Here is the code:
$(document).on('backbutton', function (ev) {
ev.preventDefault();
if (!$('#divHomeScreen').is(':visible')) {
$('.screen').hide();
$('#divHomeScreen').show();
return false;
} else {
navigator.app.exitApp();
}
});
Thanks for your help.
What I have done is dynamically add and remove the backbutton handler as needed. For example...
function showScreen()
{
$("#divHomeScreen").hide();
$(".screen").show();
$(document).on("backbutton", onBackButton);
}
function hideScreen()
{
$(".screen").hide();
$("#divHomeScreen").show();
$(document).off("backbutton", onBackButton);
}
function onBackButton()
{
hideScreen();
}
This was tested on Galaxy S3 Android 4.3 and PhoneGap 3.3.0
I am new to jQuery Mobile 1.4.5, when I try to implement changePage() triggered by swipeleft, it works perfect with following code:
$("#mypage").on("swipeleft", function(e){
log("swipeleft");
if(event.handled !== true) // This will prevent event triggering more then once
{
$.mobile.changePage('#mypage2', {transition: "slide"});
event.handled = true;
}
return false;
});
However, once the changePage() event is triggered, it can't go back until the next page is completely showed. I was wondering is it possible to do like other "swipe to change page" function e.g. Facebook slide to show friend list. I can slide to show part of target page, and the edge of page is just followed where my finger is. Instead of changing whole page
Thanks for your help.